Type and Severity of Mental Illness and Participation in Colorectal Cancer Screening

Introduction: The effectiveness of colorectal cancer screening programs depends on the participa-tion rate. This study examined the association between type and severity of mental illness and colo-rectal cancer screening participation.Methods: Between 2012 and 2017, a total of 46,919 individuals were invited to sigmoidoscopy screening in Norway, and 70,019 were invited to fecal immunochemical testing. In 2022, logistic regression was used to evaluate the association between the use of antipsychotics, anxiolytics, hyp-notics, and antidepressants in the year preceding the screening invitation and screening participa-tion, adjusted for demographic and socioeconomic factors. Defined daily doses of individual drugs were used to assess dose-response relationships.Results: Overall, 19.2% (24.8% of women, 13.4% of men) of all invitees used at least 1 psychotro-pic medication. Nonparticipation in the 2 arms combined was associated with the use of anxiolytics (60.7% in users vs 43.2% in nonusers; OR=1.53; 95% CI=1.45, 1.62) and antipsychotics (64.3% vs 43.8%; OR=1.41; 95% CI=1.30, 1.53) and increased with higher doses for both drugs. Hypnotics and antidepressants were only weakly associated with nonparticipation in higher doses. Participa-tion rates were 57.3%, 52.3%, 42.9%, and 35.4% in those prescribed 0, 1, 2, and 3-4 classes of psy-chotropic medications, respectively. The associations between the use of psychotropic medications and nonparticipation were similar for the 2 screening tests.Conclusions: These findings show significant disparities in colorectal cancer screening participation for individuals with mental illness, independent of the screening method. Moreover, screening participation varied depending on the type and severity of mental illness. Targeted interventions are warranted to ensure that people with mental illness are supported to access the benefits of colorectal cancer screening. Am J Prev Med 2023;64(1):76-85. (c) 2022 American Journal of Preventive Medicine. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).